Please note: All credit goes to Banana!
Best method for farming kills if done perfectly you can get 625 kills within 12 minutes.
How to Obtain Zombie Champion and Zombie Overseer Achievements
The Method to Get This Achievement Fast
Replay the map detox center over and over
- Use the vulcan t6 fully upgraded.
- Rush through the map as fast as possible.
- If done at a good pace you can get this every 125 kills every 2.5 minutes.
- If this is done fast you can get 1250 kills per 25 minutes.
- If you do long biohazard that gives 194 kills per 10 minutes. But if you do dtox center you can get 625 in 12.5 minutes or less. Basically 3x the amount of kills in close to the same time.
- If you were to do survival you can get 90 ish kills within 3 minutes. But this method still puts that strategy to shame.
- This method from 5000 kills to 10k takes 1.6 hours. You would have to replay this map about 40 times and if you do it within the time shown in the screenshot below. You can complete this in under 2 hours.
- Make sure you got autoheal and put the difficulty to easy in gameplay options to maximize kills.